Run Faster, Jump Higher with bionic-like power: Anywhere, Any Age. Literally one of the coolest pieces of sporting equipment available to mankind! The lightest, most advanced jumping stilts on the planet: The BW-EXTREME. Run over 20 miles per hour. Jump up to 3-5 meters high. The "Best of Line" EXTREME Model is ideal for high performance acrobatic use or as your favorite outdoor exercise. This German engineered, USA patent protected, athletic equipment has weight categories for any size. 1 year warranty on defective parts. 30 day full return for all “unused” product. The BW-EXTREME has newly designed Calf Cuffs for ease of fit and exceptional comfort. The wide strap bindings are safe and simple to tighten. Recent manufacturing upgrades have increased the quality of the carbon fiberglass leaf springs. Our new springs are light in weight yet deliver a stronger response. Please buy the size that fits your current weight category. Once your units arrive, you’ll only need to reverse the calf cuffs so the buckle is in front, raise the cuffs so the top is 1” from knee cap, then use tools to secure the placement of the cuff. Make sure the cuffs’ aluminum support tubes are secure against the side of the leg, before tightening. Do not over tighten. Are Air-Trekker jumping stilts dangerous? Anything can be dangerous if used improperly. Air-Trekkers for adults are not toys, take them seriously! Just as you're not an instant Maui north shore surfer, scratch golfer, or black diamond snowboarder, you may not want to, or be able, to do back flips on your Air-Trekkers your first day! Please take the time to learn how to properly use Air-Trekkers. Learn how to walk, fall, and easily get up. Review our guide manual and the video lessons, watch other trekkers, and attend online community forums. Step by step you WILL become more confident and when used correctly, wearing jumping stilts is no more dangerous than any other extreme sport activity. They ARE a LOT more fun! To insure your safety, we insist you put on all safety gear before using your Air-Trekkers...including but not limited to helmet, knee pads, elbow pads, and wrist guards. By purchasing or using Air-Trekkers, you accept full responsibility for any and all injury and will not hold Alpine Innovations, LLC responsible. You also agree to be 18 years of age or have consent of an adult to purchase or use Air-Trekkers